This Shared Instrumentation Grant proposal is for the purchase of the BD FACSAria Flow Cytometer Cell Sorter. This is a state-of-the-art fully digital, three laser (488nm, 633nm and 407nm) Flow Cytometer Cell Sorter. It is capable of sorting two to four populations at an acquisition rate of up to 70,000 cells per second. This request includes several options. The water recirculator will provide optimal temperature control for the sample and sorted fractions. The Automated Cell Deposition Unit (ACDU) option is an integrated cell deposition system for multi-well plate and slide sorting. The aerosol management system option will enable sorting of biologically hazardous samples. The HP XW4000 Workstation provides a powerful data management system. The new BD FACSAria cell sorter will be housed at USUHS in the Biomedical Instrumentation Center (BIC), Flow Cytometry Facility, Room G235, and will be operated and maintained by the Flow Cytometry Facility Director, Karen M. Wolcott. The Principal Investigator, William C. Gause, will provide administrative/scientific oversight in consultation with an internal advisory committee. The BD FACSAria is requested as a replacement for the current flow cytometer cell sorter, a 13-year old Beckman Coulter EPICS ELITE ESP. Many requests for sorting have been declined due to the inability of this antiquated instrument to support the needs of many research protocols, especially those of the NIH-supported investigators identified in this grant. First priority will be given to the NIH-supported scientists who are participating in this grant proposal. They include: 1.) Brumeanu, Teodor D. - Prevention of Type 1 Diabetes by soluble MHC II- peptides; 2.) Cutler, Mary Lou - Role of Ras Effectors in Mammary Differentiation; 3.) Darling, Thomas N. - Tumorigenesis in Tuberous Sclerosis; 4.) Gause, William C. - Regulation of Th2 cell commitment, differentiation, and cell cycle progression in vivo; 5.) Giam, Chou-Zen - Molecular Biology and Pathogenesis of HTLV-1; 6.) Pollard, Harvey B. - Regulation of Inflammatory Pathways in Cystic Fibrosis; 7.) Provencio, Ignacio Isolation and Characterization of Melanopsin-Containing Retinal Ganglion Cells; 8.) Schaefer, Brian C. - Antigen receptor regulation of NF-KB signaling in lymphocyte activation and tumorigenesis; 9.) Snapper, Clifford M. - Dendritic and T cells in antibacterial Ig responses; 10.) Tsokos, George C. - Regulation of lymphocyte function during Systemic Lupus Erythematosus (SLE); and 11.) Via, Charles S. - Immunopathogenesis of Lupus. It is anticipated that this group of investigators will require 95% of the total usage of the instrument. The remaining 5% will be allocated to USUHS, NIH-supported research scientists or other individuals in the USUHS community on a first come, first served basis. Sorting time may be made available to investigators outside of the USUHS community from time to time when the instrument would otherwise not be used. [unreadable] [unreadable] [unreadable]